A mathematical procedure to predict optical performance of CPCs

2016 International Conference on New Energy and Future Energy System

Yu, Y.M.^1 ; Yu, M.J.^1 ; Tang, R.S.^1

Education Ministry, Key Laboratory of Advanced Technology and Preparation for Renewable Energy Materials, Yunnan Normal University, Kunming

650500, China^1

关键词: Acceptance half angle;    Angular dependence;    Compound parabolic concentrator;    Concentrating photovoltaic systems;    Mathematical procedures;    Optical efficiency;    Optical performance;    Radiation transfer;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/40/1/012006/pdf
DOI  :  10.1088/1755-1315/40/1/012006

来源: IOP

【 摘 要 】

To evaluate the optical performance of a CPC based concentrating photovoltaic system, it is essential to find the angular dependence of optical efficiency of compound parabolic concentrator (CPC-θe) where the incident angle of solar rays on solar cells is restricted within θefor the radiation over its acceptance angle. In this work, a mathematical procedure was developed to calculate the optical efficiency of CPC-θefor radiation incident at any angle based radiation transfer within CPC-θe. Calculations show that, given the acceptance half-angle (θa), the annual radiation of full CPC-θeincreases with the increase of θeand the CPC without restriction of exit angle (CPC-90) annually collects the most radiation due to large geometry (Ct); whereas for truncated CPCs with identical θa and Ct, the annual radiation collected by CPC-θeis almost identical to that by CPC-90, even slightly higher. Calculations also indicate that the annual radiation on the absorber of CPC-θeat the angle larger than θedecrease with the increase of θebut always less than that of CPC-90, and this implies that the CPC-θebased PV system is more efficient than CPC-90 based PV system because the radiation on solar cells incident at large angle is poorly converted into electricity.